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reillymj writes "There are three known 'exploding lakes' in the world, where volcanic gases build up near the lake bottom until they suddenly fizz over, suffocating people with huge amounts of carbon dioxide. But the lakes also hold methane and one of them, Rwanda's Lake Kivu, is being actively tapped as a source of natural gas to fuel a power plant on the lake's shore. The government hopes that within two years, the plant will be covering a third of the country's needs. By siphoning off the gas, engineers simultaneously defuse a ticking time bomb in the lake and provide power to local communities."

I am a chemical engineer from South Africa. We studied this project back in the early 90's, when I worked for the South African national oil and gas exploration company. Economically, it is a no-brainer, as the gas is trivially cheap to exploit. But some corruption, and some genocide, got in the way and so now it has taken 20 years. BTW, the local bottling company wanted the CO2.

The takehome for me was the amazing measure of just how small the Rwandan economy is - a single smallish power plant can supply a third of the country's power needs. That's a pretty good measure of how "third" the third world can be. The tiny town of Lake Worth Florida is considering adding 90 MW of capacity to their city run utility's power plant. Compare that with the planned 50MW capacity for the Rwanda plant. Simple math tells me that they plan for 150MW to cover the entire country in two years. Compared with one small town in Florida. And calling Lake Worth a town is generous. It is only a couple of miles long and wide - really more of a suburb of West Palm Beach. Which is sad in its own right - a suburb of a suburb of somebody's second home. (West Palm Beach services Palm Beach, where all of the rich folks have their second or third homes).

I'm glad that you put it into perspective like that. I suspected that the natural resource was approximately the size of a football field or 2, and that Rwanda was an above average size African country.

Hmm. Before hitting submit, I decided to take a look at a map of Africa [travelnotes.org], and find the population of Rwanda [google.com]. Wow. I didn't realize how small the place was.

That being said, I'm very happy for them. This sounds like a genuine attempt at furthering themselves. Kudos. Hopefully, they'll have the innovation to try

Taking the absolute numbers really gives us ground for comparison. With a population of nearly 9 million, Rwanda is slightly more populous than New York, the largest city in the US [city-data.com]. From the fine article, Rwanda is building to a total generation capacity of 150MW. The city of New York is one of the most energy efficient in the US, [wikipedia.org] probably due to climate and housing density.

Even so, when the air conditioners kick in during the summer they can use 6.9 million megawatt hours [theepochtimes.com] in a single month.

Thanks for the comparison to NY. I especially like the "6.9 million" number. At first, I thought that it was only 3 more zeros than Rwanda's needs, but not even close.

That being said, now I'm even more excited about this, because it is really obvious that Rwanda is "just starting out" in comparison to us. I hope that they take this initiative and develop it, to start exporting technology to the rest of the world. Maybe they can use their influence to push the rest of Africa into this century.

Seriously? Parent is not a troll, people. The link isn't all that informative, but it also isn't goatse.

I do remember hearing stories about outgassing lakes like this many years ago. It was thought that submerging a giant straw and/or circulating water across the thermocline would allow the CO2 to escape relatively safely. As I recall, the article I read about it ended along the lines of 'oh, how terrible it is that nobody will give $x0,000 to make this lake safe!'. I guess now that it is profitable the loc

I think that I figured out a possible problem with the moderation system.

Perhaps moderators from different countries are moderating "us". That particular comment wasn't negative, controversial, or political. It is quite a ways down the page. It has a very positive tone. I can only assume that somebody from a foreign country looked at the 2 words, "grease" and "traps", and saw negative connotations. I tutor ESL, and try to learn languages, so I am keenly aware that we can't put 2 words together and then auto

We also do it with landfill off gassing. It takes a fairly sizable landfill, but the gas is going into the atmosphere anyways, may as well trap it and burn it.

It's interesting that you mention that. It reminds me that we racist, wasteful, redneck, white bred 'Zonies [urbandictionary.com]' (none of these are my personal adjectives, but I've heard every one of them too many times to keep track), have a number of these systems in place. In addition to the landfill methane capture [wapa.gov] systems (which, last I checked, were somewhat experi

You don't get to live in Phoenix, do you? Nothing is comparable to the awesomeness that is Phoenix...

Ahhh, but I DO get to live in Phoenix. Valley of the Sun. Land of the broken dams with burst Goodyear Tire rubber bladders, where the Mexican drug cartels have put a $1 mil price on the local sheriff's head... ah yes, welcome to my home.

Statistically I certainly do use 2-3 times less resources than you, for very comparable quality of life.

Statistically, you're a 16 year old nerd posting from you Mom's basement. Really. How stupid is that? Statistically then, I have access to 2-3 times the resources than you have, which makes for a significantly better quality of life for me. And that's just as stupid.Then again, if you knew anything, you'd know that the irrigation is for farming. Better make sure you don't wear any Pima cotton shirts. Whil

Ahhh, so after all you don't get that averages, both resource consumption & the results, is what matters here... And no, you don't make use of those extra resources you waste it while chasing...the same results [wikipedia.org] (admittedly my place is beyond what is sustainable, too; but at least not nearly so wildly)

Right, which is why there's very little drawback to it. You burn it or you capture it and you burn it in a generator or use it in furnaces. In all cases you're somewhat better off for the reason you cite. But, if you use it for heating homes or generating electricity that's somewhat less capacity that you need from elsewhere.

Wrong, it's a net negative, the contribution has already been made, this would reduce it by the difference. And probably even more as you can always trap the CO2 and use it for soda instead of generating C02 for that purpose.

The second thing you said contradicts the first thing, because it would be meaningless to consider them without their mutual context. The question can only be understood as a comparison of the two outcomes.

The third thing you said contradicts the first and second things, but only if the second thing is derived from the first thing, because it is meaningless to extrapolate the outcomes without the statistical evidence to prove the contextual comparison. Wait what am I saying?

The party to the third part, in reference to the third party's part in the second part, which in part parts with the whole of the first part but not the second part, involves only the first party's involvement with the second and third parts, which are parts of an overarching first part that may partly be to blame for part or the whole of the issue at hand, the first part.

It would be released at some point anyway (methane and also dissolved CO2), but in a much less controllable, much less pleasant way [wikipedia.org] (lake Kivu is mentioned). By siphoning it out gradually, you can not only deal with the danger, but also get some useful energy as a bonus.

Also, methane is a much more potent greenhouse gas than CO2, so burning it prior to release actually lessens overall impact.

I have been advocating this position since I first learned about the exploding lakes from the science channel in 8th grade! I am very glad someone finally got around to doing it. If only there was something they could do to stop the carbon dioxide eruptions.

There is a big difference, venting it into the atmosphere still releases it into the atmosphere. I have been advocating collecting it and using it to generate power in these areas. I am glad they are finally doing something with it.

There's very little difference - you can't do all that much with CO2 (except perhaps some small turbine at the end of shaft, which I'm pondering in other comment), which is by far the main culprit in those lakes & for which you were most hoping for a solution...well, it's here for some time. It's all released into the atmoshpere anyway; just in a controlled, more gradual fasion & finding some use in the process.

I have been advocating this position since I first learned about the exploding lakes from the science channel in 8th grade! I am very glad someone finally got around to doing it. If only there was something they could do to stop the carbon dioxide eruptions.

Worse than the CO2 is the methane. As a greenhouse gas it is more than 20 tymes as potent as carbon dioxide, and it no less dangerous if breathed in.

Yea, because the CO2 is just a white cloud that kills everyone, but Methane is explosive. The lake would literally explode in a fireball. Kinda makes you realize where some ancient myths came from. Reality is always more fucking awesome than the shit people make up.

because the CO2 is just a white cloud that kills everyone, but Methane is explosive. The lake would literally explode in a fireball.

While the CO2 would be dangerous, the methane would need to be heated or sparked to ignition. A volcanic eruption could cause such an event, but that isn't the only thing that could trigger a Limnic eruption. In essence, it's not a certainty that the lake would 'explode in a fireball'.

Large quantities of nearly pure methane drifting over villiages that aren't exactly high tech. I wouldn't doubt that someone has a fire going. Plus, methane spontaneously combusts in the presence of oxygen, as the heat needed is lower than room temp. Especially lower than African regular temp.

Because you're not using methane, you are using a combination of different gaseous organic compounds. Methane is the most simple of them, consisting of a single carbon and 4 hydrogen. Other natural gasses, including propane, octane, heptane, among others are also present in the mix, kind of like crude oil containing many different organic carbon chains. Pure methane has the lowest temperature for combustion that is below room temperature, in a mix where it is the minority it will not explode. Just ask an

You are wrong.
Natural gas at the wellheads is often 85% to 95% methane, with a tendency to have carbon dioxide and nitrogen, among other things, mixed in. The suppliers tend to remove the non-combustibles as well as the ethane, propane, butane, etc. from the gas delivered to you, which will usually be almost pure methane. (They can sell most of the non-methane products separately for a profit, even, in some cases, the carbon dioxide.)
Also, Methane has a narrow range of flammability, from 4%+ to 17%- in a

CO2 is not dangerous at all if breathed in so I'm not sure what you're implying there.

It is dangerous in high enough concentations. I believe that the OSHA limit for 8-hr average exposure is 5,000 ppm and it is considered acutely toxic at levels above 4% or so.

Put that way everything is dangerous in high enough concentrations. Methane will cause asphyxiation in lower concentrations than CO2 will. For that matter carbon monoxide, CO, is more dangerous than carbon dioxide, ask NASCAR [nascar.com] drivers.

Well for one, that's not a huge pressure head to generate electricity on a large scale. When you see dams they are so tall to generate enough pressure to make large scale energy harvesting feasible. It's also possible that by trying to harvest the energy, you'll disrupt the siphon's flow; although I don't have any backup for that claim, it's just a guess.

Secondly, I'd wager that if they're pulling the methane out of the lake and burning it that you remove most of the source for the dissolved CO2 anyway.

Electricity generation doesn't have to be on a large scale (per generator) after all. The smaller lake , Nyos, is quite remote & with not many people nearby; what some small installation could provide should be plenty. Lake Kivu is big; with a need, really, for many "pumps."

With a self-sustaining fountain of 50+ meters at a small Nyos siphon, the flow should be powerful enough.

quote 1;The world's only two other known "exploding lakes", Monoun and Nyos, both in Cameroon, overturned in the 1980s. The clouds of carbon dioxide that burst through from the deep water left about 1,800 people dead from asphyxiation. But Lake Kivu is nearly 2,000 times larger than Lake Nyos, and is in a far more densely populated area. Cindy Ebinger, a professor of earth sciences at the University of Rochester in the US, who co-authored a study earlier this year that described Kivu as possibly "one of the most dangerous lakes in the world", said: "You don't even want to think about the scale of the devastation that could occur."quote 2;To harvest the methane, heavy water is sucked up through a pipe to the barge, where the liquid and gases are separated. The gas then enters a "scrubber" that separates the methane and carbon dioxide. Ebinger said reducing the overall concentration of gas in the water was a positive move, but warned that more studies were urgently needed to assess the potential environmental impact, especially relating to the unused water and carbon dioxide pumped back into Lake Kivu from the barges.quote 3;"With so many projects, if you don't understand everything, you can solve one problem and create three more," she said.quote 4;Regardless, Rwanda is proceeding at great speed".

Erm, is it just me or is there a lengthy "whatcouldpossiblygowrong" in there, Mrs. Ebinger?

What are the possibilities of turning a somewhat "normal" lake (probably near enough to a volcano) into an exploding one? Politicians could even use the "think on the children" wildcard to justify that, if is somewhat possible with not so high investment.

turning a somewhat "normal" lake (probably near enough to a volcano) into an exploding one?

It's already being done. The gas industry is experiencing a boom in the US at the moment because NG creates less CO2 than coal when burned and new recovery techniques are making known reserves economically recoverable. One of these new techniques is Hydraulic Fracturing.

Fracking breaks rock formations to release reservoir contents for recovery. One consequence of this is that nearby aquifers (subsurface water) can become contaminated with hydrocarbons. This has produced cases of benzine flavored wate

Don't forget that the chemicals that they are pumping in to break up the rock formation include carcinogens, neurotoxins, and other nasty, nasty chemicals. They 'assume' they will not come back out and contaminate the aquifers. This is a bad, bad practice.

Cue green hysterics and indignant congress folk. Some negligent company will be singled out for public outrage. Some clutch of lawyers in a government agency will be found snoozing and be given a pass.

This sounds familiar...a little company called BP, and a government agency called the Minerals Management Agency, if I recall. It's how all these things go, even though there usually are others to blame aside from the negligent company, and the government agency given a pass might just end up reorganized or renamed.

The dam is the largest operating hydroelectric facility in terms of annual generating capacity, generating 94.7 TWh in 2008 and 91.6 TWh in 2009, while the annual generating capacity of the Three Gorges Dam was 80.8 TWh in 2008 and 79.4 TWh in 2009[1].

The dam is the largest operating hydroelectric facility in terms of annual generating capacity, generating 94.7 TWh in 2008 and 91.6 TWh in 2009, while the annual generating capacity of the Three Gorges Dam was 80.8 TWh in 2008 and 79.4 TWh in 2009

It doesn't help trying to compare TWh and TW as we have no clue how many hours the things are running for.Hydro is perfect for covering peaks because it comes up to full capacity within minutes instead of the hours required to start up with coal/oil or nuclear, so it is very likely that not all of those hydro units are not running all of the time.

Hydro is perfect for covering peaks because it comes up to full capacity within minutes instead of the hours required to start up with coal/oil or nuclear, so it is very likely that not all of those hydro units are not running all of the time.

Natural gas also is good for peak generation, for the same reason, electrical generation in natural gas power plants can be quickly ramped up if not already at full production.

"The 12 south side generators are also in operation. No. 22 began operation on June 11, 2007 and No. 15 started up on October 30, 2008.[3] The sixth (No. 17) began operation on December 18, 2007, raising capacity to 14.1 GW, finally surpassing Itaipu (14.0 GW), to become the world's largest hydropower plant.[32][33][34][35]"

What struck me in TFA was the scale of the project. 3.6 MW will provide 4% of the whole country's electricity needs.

Except it doesn't say that. TFA says that it supplies "more than 4% of the country's entire supply" not it's needs. Currently only "one in 14 homes have access to electricity". Demand will rise to drive electrical needs higher.

To put it into perspective, the largest power plant in the world, Itaipu dam, has a 14000 MW capacity.

3BR, 2BA brick house in great neighborhood, large porches and patios, 1 acre fenced yard with pool, conveniently located near schools, bus lines, restaurants, lake that occasionally explodes and kills everyone, city parks. New carpet! $175,000.